AUSTRALIA—A group of 100 people has banded together to sue Pfizer Australia and Aspen Pharmacare, claiming they were afflicted with compulsive disorders that caused them to engage in uncontrollable addictive behavior after taking prescription drugs to treat tremors associated with Parkinson's Disease.

“The case will take the form of a class action in the Federal Court,” reported the Sydney Morning Herald. “The group includes people who sustained losses of hundreds of thousands of dollars and were involved in family breakdowns as a result of compulsive gambling allegedly linked to drugs they took between 1997 and last year. Most of the claimants developed gambling addictions but a few exhibited compulsive sexual behavior such as looking at pornography on the internet.”

The drugs associated with the claims are Cabaser (Pfizer Australia) and Permax (Aspen Pharmacare). The plaintiffs say the drug companies either failed to conduct enough research on side effects or heed research already conducted.

A study published in the May issue of Archives of Neurology warned, “Dopamine agonist treatment in PD (Parkinson's Disease) is associated with 2- to 3.5-fold increased odds of having an ICD (impulse control disorder).

However, the same study also found that the Dopamine association "represents a drug class relationship across ICDs. The association of other demographic and clinical variables with ICDs suggests a complex relationship that requires additional investigation to optimize prevention and treatment strategies."

Of the 13.6 percent of patients who were identified as being affected by the use of the drugs, the exhibited impulse control disorder included gambling (5 percent), compulsive sexual behavior (3.5 percent), compulsive buying (5.7 percent) and binge-eating (4.3 percent).

The case is not without precedent, according to the Herald. In a test case in July 2008, a jury in Minnesota awarded $8.2 million to a man who became a compulsive gambler after using Mirapex (made by Boehringer Ingelheim) to treat his Parkinson's disease. Other lawsuits are being considered in Britain, Canada and France.

A hearing on the suit is scheduled for Friday. As of Thursday, the drug companies had yet to be informed of the action, according to the paper.